Fabric treatment



Patented Mar. 9, 1943 2,313,173 FABRIC TREATMENT George Schneider,Montclair, N. J., and Joseph E. Bludworth and Cyril M. Croft,Cumberland, Md., assignors to Oelanese Corporation of America, acorporation of Delaware No Drawing. Application May 25, 1940, Serial No.337,198

4 Claims.

This invention relates to the removal of creases from fabrics andrelates more particularly to the removal of creases from fabrics whichare composed of or contain yarns which are thermoplastic in nature.

An object of this invention is the rapid and economic removal of creasesfrom fabrics.

Another object of this invention is the removal of creases from fabricswhich contain yarns made of thermoplastic materials and moreparticularly yarns of organic derivatives of cellulose.

Still another object of this invention is the removal of said creaseswithout affecting the strength, elasticity and other physicalcharacteristics of the fabrics or the individual yarns composing thefabrics.

Other objects of this invention will apepar hereinafter from thefollowing detailed description.

In the preparation of organic derivative of cellulose fabrics, and otherfabrics composed of or containing thermoplastic materials for commercialuse after they are woven, the fabrics are given various treatmentsbefore they are in a commercially acceptable condition. Such treatmentsinvolve the washing, scouring, de-sizing, dyeing, printing, embossing,etc., of the fabric, and during the course of these various operationsin which the fabric is alternately wetted and dried, it frequentlyhappens that the fabric becomes creased to a greater or lesser extentdepending on the amount of working it has been subjected to. When largequantities of fabrics are being processed the removal of creases fromthe materials becomes a serious problem. While the creases may beremoved by ironing the cloth under the pressure of a heated surface orsurfaces, such a process requires much individual handling.

We have now discovered that creases may be easily and permanentlyremoved from fabrics made of or containing yarns of organic derivativesof cellulose or other thermoplastic materials if the creased fabrics arestretched and then subjected to the action of heat while they are in thestretched condition. Not only are the creases in the fabric thereycompletely removed, but the action of the applied heat has the addedeffect of tautening and strengthening the fabric. These desirable andbeneficial effects are achieved without applying a heated surfacedirectly to the fabric as is the case when fabrics are ironed in theordinary manner with a hot metal surface or with heated, cloth-coveredrolls.

In accordance with our invention, we apply heat to the fabric by passingit in close proximity to a source of heat or in some cases, by passingthe heat source near the surface of a stationary fabric. In this mannerour beneficial results are obtained by the radiation and convection ofthe heat to the fabric and not, as in the ordinary case in which fabricsare ironed, by pressure and the direct conduction of the necessary heat.

The temperature of the heating zone to which the stretched or tautenedfabric is subjected may vary from about 250 F. to about 900 F. but, wepreferably expose the fabric to a source of heat in such a manner thatthe temperature at the fabric heating zone itself is about 450 F. Whenthe stretched fabric is thus exposed to a temperature of about 450 F.the time during which it is so exposed is generally about 5 seconds.When the fabric is exposed to higher or lower temperatures the necessarytime of exposure will of course vary and will be from about 1 6 to about15 seconds. Shorter periods of exposure will give desirable resultswhere the temperatures are above 450 F., while longer periods ofexposure are necessary when the temperature is below 450 F.

To obtain the desired temperature at the fabric heating zone, the sourceof heat is generally operated at temperatures varying from about 800 F.to about 1500" F., but we preferably maintain the heat source attemperatures of from about 1000 F. to about 1200 F. Where the heatsource is maintained at from about 1000 F. to about 1200 F. thetemperature in the heating zone about one inch from the heat source willbe about 450 F. When the heat source is maintained at the sametemperature, a heating zone about two inches from the heat source is ata temperature of about 250 F. It is obvious therefore, that if thedistance of the fabric from the heat source is held constant, the lengthof time during which it must be exposed will be in direct relation tothe temperature. When the distance from the heat source is varied, thetime and temperature relation will also vary, since the further thefabric is away from the heat source employed, the lower will be thetemperature of the fabric.

In some cases where the fabric is heavy and closely woven and is deeplycreased, it is necessary to operate at the higher temperatures andexpose the fabric for longer periods of time. On the other hand wherethe fabric is light or where it is not deeply creased the time ofexposure will be shorter and the temperature to which it is exposed willbe lower.

Various sources of heat are suitable. Electric radiant heaters, electriclight globes, gas heated metal surfaces superheated steam in coilsheated to the desired temperature, or heated mercury vapor in coils areall excellent heat sources whose temperatures may be closely controlled.Besides steam and mercury vapor, other liquids such as diphenyl ether,etc., commonly used as heat transfer mediums may also be utilized. Thechoice of a heat source is an arbitrary one and is only determined byfactors such as cost and convenience, the primary object being a heatsource subject to accurate control.

The fabrics to which our process of crease removal may be applied arethose fabrics which are composed of or contain yarns of organicderivatives of cellulose or other thermoplastic materials. Among theorganic derivative of cellulose fabrics from which creases may beremoved are fabrics composed of yarns of organic esters and organicethers of cellulose. Such organic esters as cellulose acetate, cellulosepropionate, cellulose butyrate and mixed esters as celluloseacetate-proprionate are suitable as well as such organic ethers ofcellulose as ethyl cellulose, methyl cellulose and benzyl cellulose.Fabrics composed of other thermoplastic materials such as those composedof yarns of synthetic linear polyamide condensation products (nylon) orsynthetic resins such as vinyl acetate-vinyl chloride copolymers mayalso be treated in accordance with our process. Creases may also beremoved from fabrics which are in part composed of thermoplastic yarnsand in part mixed with other textile materials such as silk, wool,cotton and the regenerated cellulose types of artificial fibers.

The material may be stretched or tautened in any suitable manner. Intreating large quantities of fabric it is desirable to stretch thefabric on a tenter frame but where only small areas are to be treatedthose areas alone may be tautened between a pair of flexible concentriccircular fabric frames in a manner similar to that in which fabric isheld upon which a design is to be embroidered.

To further illustrate our invention but without being limited theretothe following examples are given:

- Example I A creased taffeta fabric woven from cellulose acetate yarnsis stretched tightly over a frame and held so as not to allow anyslippage from the edge of the piece. The fabric is then passed at adistance of about one inch from a heater which is heated by electricityto a temperature of from 1000 F. to 1200 F. so that the temperature atthe face of the fabric is about 450 F. The cloth is exposed to thistemperature for not more than about 5 seconds. When removed from theframe it is noted that the creases are completely removed from thefabric and there is no tendency for the creases to return to the fabric.

Example II A light ninon fabric containing creases which is woven fromcellulose acetate yarns is stretched over a tenter frame and held inposition. It is then passed at a distance of 1 inch from an electricradiant heater held at a temperature of about 1200" F. The temperatureat the face of the fabric about 1 inch from the heater is about 450 .F.The cloth is exposed to this temperature for not more than 2 seconds.When removed from the tenter frame the'fabric is flat and free fromcreases.

It is to be understood that the foregoin detailed description is givenmerely by way of iilustration and that many variations may be madetherein without departing from the spirit of our invention.

Having described our invention, what we desire to secure by LettersPatent is:

1. Process for the removal of creases from fabrics containing yarns of athermoplastic material without the application thereto of pressure witha heated surface, which comprises subjecting the tautened fabric to atemperature of from 250- 900 F. for a period of from 01-15 seconds, themaximum moisture content of the fabric before the heat treatment beingits normal moisture regain.

2. Process for the removal of creases from fabrics containing yarns of athermoplastic organic derivative of cellulose without the applicationthereto of pressure with a heated surface, which comprises subjectingthe tautened fabric to a temperature of from 250-900 F. for a period offrom 01-15 seconds, the maximum moisture content of the fabric beforethe heat treatment being its normal moisture regain.

3. Process for the removal of creases from fabrics containing yarns ofcellulose acetate without the application thereto of pressure with aheated surface, which comprises subjecting the tautened fabric to atemperature of from 250-900 F. for a period of from 0.1-15 seconds, themaximum moisture content of the fabric before the heat treatment beingits normal moisture regain.

4. Process for the removal of creases from fabrics containing yarns ofcellulose acetate without the application thereto of pressure with aheated surface, which comprises subjecting the tautened fabric to atemperature of about 450 F. for a period of about 5 seconds, the maximummoisture content of the fabric before the heat treatment being itsnormal moisture regain.

GEORGE SCHNEIDER. JOSEPH E. BLUDWORTH. CYRJL M. CROFT.

